Non-Specific Disease Resistance

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Module: Disease Resistance
Activity: Animations
Title: Non-Specific Disease Resistance

Introduction

1. Name five general non-specific defense mechanisms that act quickly to fight a wide variety of “invaders.”

Barriers

2. a. Name five physical barriers that prevent invasion by microbes.

b. Name five chemical barriers that prevent invasion by microbes.

3. Click on the eye to investigate defense mechanisms found there. Describe the protective contribution of lacrimation.


4. Click on the respiratory mucosa to investigate defense mechanisms found there.

a. Describe the defensive role of nasal hair.

b. Describe the defensive role of lymph tissue located in the airway (MALT).

c. Describe the defensive role of pseudostratified ciliated columnar epithelium lining the respiratory airway.

d. Describe the defensive role of alveolar macrophages.

5. Click on the skin to investigate defense mechanisms found there.

a. Describe the defensive role of the keratinized epidermis.

b. Describe the defensive role of sebum.

c. Describe the defensive role of perspiration.

d. Describe the defensive role of macrophages in the skin.

6. Click on the digestive mucosa to investigate defensive mechanisms found there.

a. Describe the defensive role of lymphocytes in the digestive tract.

b. Describe the defensive properties of saliva.

c. Describe the defensive properties of stomach acids.

d. How does peristaltic movement contribute to pathogen resistance?

Antimicrobial Substances

7. a. Describe the defensive role of interferons.

b. Why are interferons non-specific mechanisms?

8. a. Define the complement system.

b. What is the function of the complement system?


9. a. Describe the classical complement pathway.

b. Describe how complement proteins can combine to form systems such as the MAC that contribute to pathogen resistance.


10. Describe the alternative complement pathway.


Cellular Defenses

11. a. Natural killer cells are a type of lymphocyte. Explain their function.

b. Where are natural killer cells found?

c. Why are natural killer cells a non-specific mechanism?

d. Describe the two ways natural killer cells kill pathogen cells.

12. Describe the defensive role of:

a. Neutrophils

b. Monocytes


13. Describe the sequential steps of phagocytosis.

chemotaxis

adherence

ingestion

digestion

killing

exocytosis

14. In what ways can pathogens “fight back” against immune mechanisms?

Inflammation

15. What is the function of the inflammatory response?

16. Describe the steps of inflammation.

Vasodilation & capillary permeability

Neutrophil & Monocyte Migration

Tissue Repair


Fever

17. a. How is fever induced?

b. Describe how fevers can be beneficial.
interferon production
bacterial enzyme damage
repair mechanisms